In a toning process for adapting colors to a target color presented by the instructions of customers is usually performed via production of around 3 different color samples in the case of CCM toning, or via production of an around 3 to 5 different color samples in the case of visual toning. Regarding precision on CCM by which simulated color is matched to the target color, when CCM correction toning is effected, the color difference is gradually decreased necessarily and, finally, the target sample can be almost reproduced. However, in a coloring process in which a colored product is obtained based on the color mixing determined by CCM toning or visual toning, there arises a problem on the reproducibility in a coloring step due to the influence of the measuring error or the use of poor color reproducibility agents or the like. When the reproducibility in a coloring step including the measuring error or the like is deteriorated, the color difference is not converged beyond that reproducibility. When colors of a colored product (final sample numbered product) produced according to CCM or visual color matching are not consistent with the target color, there is a problem on the reproducibility in many cases.
Previously, when the reproducibility of colors in a coloring step is examined, for example, when the reproducibility is examined on sample No. 3 among a 5 samples group, the sample color has to be produced a few times based on the relevant color mixing. In addition, when there is no problem regarding the reproducibility of sample No.3, the similar examination has to be further performed on other sample No. product for which kinds of coloring agents are the same but their mixing rate is different.
However, the production of a sample for confirmation of the reproducibility in the toning work is laborious in the sample production and is actually impossible in respect of the efficiency. For that reason, if the results of the actually measured color difference of a sample product produced in a toning process such as CCM toning or visual toning as well as the reproducibility are rapidly and simultaneously displayed on a computer screen, determination whether toning is to be continued or toning should be stopped can be done earlier and, at the same time, materials for determinating the strategy can be obtained, being advantageous. In addition, when there is a problem on the reproducibility of the development of a particular coloring agent, if what coloring agent is mixed to what extent is known, the cause can be investigated and, at the same time, the production efficiency can be enhanced, being advantageous.
Therefore, an object of the present invention is to provide a method for evaluating the reproducibility of a toning sample, which can rapidly and simply perform determination whether the toning work is to be continued or not, by displaying the actually measured color difference of a sample product produced in a toning process such as CCM toning and visual toning and the reproducibility. Another object of the present invention is to provide a method for presuming a component such as a coloring agent mixed into a toning sample, when the abnormal sample is perceived in the method for evaluating the reproducibility of the sample, and a method for presuming its mixed amount.